Example #1
1
    def _init_training(self, das_file, ttree_file, data_portion):
        """Initialize training.

        Store input data, initialize 1-hot feature representations for input and output and
        transform training data accordingly, initialize the classification neural network.
        """
        # read input
        log_info('Reading DAs from ' + das_file + '...')
        das = read_das(das_file)
        log_info('Reading t-trees from ' + ttree_file + '...')
        ttree_doc = read_ttrees(ttree_file)
        trees = trees_from_doc(ttree_doc, self.language, self.selector)

        # make training data smaller if necessary
        train_size = int(round(data_portion * len(trees)))
        self.train_trees = trees[:train_size]
        self.train_das = das[:train_size]

        # add empty tree + empty DA to training data
        # (i.e. forbid the network to keep any of its outputs "always-on")
        train_size += 1
        self.train_trees.append(TreeData())
        empty_da = DialogueAct()
        empty_da.parse('inform()')
        self.train_das.append(empty_da)

        self.train_order = range(len(self.train_trees))
        log_info('Using %d training instances.' % train_size)

        # initialize input features/embeddings
        if self.tree_embs:
            self.dict_size = self.tree_embs.init_dict(self.train_trees)
            self.X = np.array([self.tree_embs.get_embeddings(tree) for tree in self.train_trees])
        else:
            self.tree_feats = Features(['node: presence t_lemma formeme'])
            self.tree_vect = DictVectorizer(sparse=False, binarize_numeric=True)
            self.X = [self.tree_feats.get_features(tree, {}) for tree in self.train_trees]
            self.X = self.tree_vect.fit_transform(self.X)

        # initialize output features
        self.da_feats = Features(['dat: dat_presence', 'svp: svp_presence'])
        self.da_vect = DictVectorizer(sparse=False, binarize_numeric=True)
        self.y = [self.da_feats.get_features(None, {'da': da}) for da in self.train_das]
        self.y = self.da_vect.fit_transform(self.y)

        # initialize I/O shapes
        self.input_shape = [list(self.X[0].shape)]
        self.num_outputs = len(self.da_vect.get_feature_names())

        # initialize NN classifier
        self._init_neural_network()
    def _init_training(self, das_file, ttree_file, data_portion):
        """Initialize training.

        Store input data, initialize 1-hot feature representations for input and output and
        transform training data accordingly, initialize the classification neural network.
        """
        # read input
        log_info('Reading DAs from ' + das_file + '...')
        das = read_das(das_file)
        log_info('Reading t-trees from ' + ttree_file + '...')
        ttree_doc = read_ttrees(ttree_file)
        trees = trees_from_doc(ttree_doc, self.language, self.selector)

        # make training data smaller if necessary
        train_size = int(round(data_portion * len(trees)))
        self.train_trees = trees[:train_size]
        self.train_das = das[:train_size]

        # add empty tree + empty DA to training data
        # (i.e. forbid the network to keep any of its outputs "always-on")
        train_size += 1
        self.train_trees.append(TreeData())
        empty_da = DA.parse('inform()')
        self.train_das.append(empty_da)

        self.train_order = range(len(self.train_trees))
        log_info('Using %d training instances.' % train_size)

        # initialize input features/embeddings
        if self.tree_embs:
            self.dict_size = self.tree_embs.init_dict(self.train_trees)
            self.X = np.array([
                self.tree_embs.get_embeddings(tree)
                for tree in self.train_trees
            ])
        else:
            self.tree_feats = Features(['node: presence t_lemma formeme'])
            self.tree_vect = DictVectorizer(sparse=False,
                                            binarize_numeric=True)
            self.X = [
                self.tree_feats.get_features(tree, {})
                for tree in self.train_trees
            ]
            self.X = self.tree_vect.fit_transform(self.X)

        # initialize output features
        self.da_feats = Features(['dat: dat_presence', 'svp: svp_presence'])
        self.da_vect = DictVectorizer(sparse=False, binarize_numeric=True)
        self.y = [
            self.da_feats.get_features(None, {'da': da})
            for da in self.train_das
        ]
        self.y = self.da_vect.fit_transform(self.y)

        # initialize I/O shapes
        self.input_shape = [list(self.X[0].shape)]
        self.num_outputs = len(self.da_vect.get_feature_names())

        # initialize NN classifier
        self._init_neural_network()
Example #3
0
    def __init__(self, cfg):
        self.cfg = cfg
        self.language = cfg.get('language', 'en')
        self.selector = cfg.get('selector', '')

        self.mode = cfg.get('mode', 'tokens' if cfg.get('use_tokens') else 'trees')

        self.da_feats = Features(['dat: dat_presence', 'svp: svp_presence'])
        self.da_vect = DictVectorizer(sparse=False, binarize_numeric=True)

        self.cur_da = None
        self.cur_da_bin = None

        self.delex_slots = cfg.get('delex_slots', None)
        if self.delex_slots:
            self.delex_slots = set(self.delex_slots.split(','))
Example #4
0
    def __init__(self, cfg):
        super(EmbNNRanker, self).__init__(cfg)
        self.emb_size = cfg.get('emb_size', 20)
        self.nn_shape = cfg.get('nn_shape', 'ff')
        self.normgrad = cfg.get('normgrad', False)

        self.cnn_num_filters = cfg.get('cnn_num_filters', 3)
        self.cnn_filter_length = cfg.get('cnn_filter_length', 3)

        # 'emb' = embeddings for both, 'emb_trees' = embeddings for tree only, 1-hot DA
        # 'emb_tree', 'emb_prev' = tree-only embeddings
        self.da_embs = cfg.get('nn', 'emb') == 'emb'

        self.tree_embs = TreeEmbeddingExtract(cfg)

        if self.da_embs:
            self.da_embs = DAEmbeddingExtract(cfg)
        else:
            self.da_feats = Features(['dat: dat_presence', 'svp: svp_presence'])
            self.vectorizer = None
Example #5
0
    def __init__(self, cfg):
        super(EmbNNRanker, self).__init__(cfg)
        self.emb_size = cfg.get('emb_size', 20)
        self.nn_shape = cfg.get('nn_shape', 'ff')
        self.normgrad = cfg.get('normgrad', False)

        self.cnn_num_filters = cfg.get('cnn_num_filters', 3)
        self.cnn_filter_length = cfg.get('cnn_filter_length', 3)

        # 'emb' = embeddings for both, 'emb_trees' = embeddings for tree only, 1-hot DA
        # 'emb_tree', 'emb_prev' = tree-only embeddings
        self.da_embs = cfg.get('nn', 'emb') == 'emb'

        self.tree_embs = TreeEmbeddingExtract(cfg)

        if self.da_embs:
            self.da_embs = DAEmbeddingExtract(cfg)
        else:
            self.da_feats = Features(['dat: dat_presence', 'svp: svp_presence'])
            self.vectorizer = None
Example #6
0
class RerankingClassifier(TFModel):
    """A classifier for trees that decides which DAIs are currently represented
    (to be used in limiting candidate generator and/or re-scoring the trees)."""
    def __init__(self, cfg):

        super(RerankingClassifier, self).__init__(scope_name='rerank-' +
                                                  cfg.get('scope_suffix', ''))
        self.cfg = cfg
        self.language = cfg.get('language', 'en')
        self.selector = cfg.get('selector', '')
        self.tree_embs = cfg.get('nn', '').startswith('emb')
        if self.tree_embs:
            self.tree_embs = TreeEmbeddingClassifExtract(cfg)
            self.emb_size = cfg.get('emb_size', 50)
        self.mode = cfg.get('mode',
                            'tokens' if cfg.get('use_tokens') else 'trees')

        self.nn_shape = cfg.get('nn_shape', 'ff')
        self.num_hidden_units = cfg.get('num_hidden_units', 512)

        self.passes = cfg.get('passes', 200)
        self.min_passes = cfg.get('min_passes', 0)
        self.alpha = cfg.get('alpha', 0.1)
        self.randomize = cfg.get('randomize', True)
        self.batch_size = cfg.get('batch_size', 1)

        self.validation_freq = cfg.get('validation_freq', 10)
        self.max_cores = cfg.get('max_cores')
        self.cur_da = None
        self.cur_da_bin = None
        self.checkpoint_path = None

        self.delex_slots = cfg.get('delex_slots', None)
        if self.delex_slots:
            self.delex_slots = set(self.delex_slots.split(','))

        # Train Summaries
        self.train_summary_dir = cfg.get('tb_summary_dir', None)
        if self.train_summary_dir:
            self.loss_summary_reranker = None
            self.train_summary_op = None
            self.train_summary_writer = None

    def save_to_file(self, model_fname):
        """Save the classifier  to a file (actually two files, one for configuration and one
        for the TensorFlow graph, which must be stored separately).

        @param model_fname: file name (for the configuration file); TF graph will be stored with a \
            different extension
        """
        model_fname = self.tf_check_filename(model_fname)
        log_info("Saving classifier to %s..." % model_fname)
        with file_stream(model_fname, 'wb', encoding=None) as fh:
            pickle.dump(self.get_all_settings(),
                        fh,
                        protocol=pickle.HIGHEST_PROTOCOL)
        tf_session_fname = re.sub(r'(.pickle)?(.gz)?$', '.tfsess', model_fname)
        if hasattr(self, 'checkpoint_path') and self.checkpoint_path:
            self.restore_checkpoint()
            shutil.rmtree(os.path.dirname(self.checkpoint_path))
        self.saver.save(self.session, tf_session_fname)

    def get_all_settings(self):
        """Get all settings except the trained model parameters (to be stored in a pickle)."""
        data = {
            'cfg': self.cfg,
            'da_feats': self.da_feats,
            'da_vect': self.da_vect,
            'tree_embs': self.tree_embs,
            'input_shape': self.input_shape,
            'num_outputs': self.num_outputs,
        }
        if self.tree_embs:
            data['dict_size'] = self.dict_size
        else:
            data['tree_feats'] = self.tree_feats
            data['tree_vect'] = self.tree_vect
        return data

    def _save_checkpoint(self):
        """Save a checkpoint to a temporary path; set `self.checkpoint_path` to the path
        where it is saved; if called repeatedly, will always overwrite the last checkpoint."""
        if not self.checkpoint_path:
            path = tempfile.mkdtemp(suffix="", prefix="tftreecl-")
            self.checkpoint_path = os.path.join(path, "ckpt")
        log_info('Saving checkpoint to %s' % self.checkpoint_path)
        self.saver.save(self.session, self.checkpoint_path)

    def restore_checkpoint(self):
        if not self.checkpoint_path:
            return
        self.saver.restore(self.session, self.checkpoint_path)

    @staticmethod
    def load_from_file(model_fname):
        """Load the reranker from a file (actually two files, one for configuration and one
        for the TensorFlow graph, which must be stored separately).

        @param model_fname: file name (for the configuration file); TF graph must be stored with a \
            different extension
        """
        log_info("Loading reranker from %s..." % model_fname)
        with file_stream(model_fname, 'rb', encoding=None) as fh:
            data = pickle.load(fh)
            ret = RerankingClassifier(cfg=data['cfg'])
            ret.load_all_settings(data)

        # re-build TF graph and restore the TF session
        tf_session_fname = os.path.abspath(
            re.sub(r'(.pickle)?(.gz)?$', '.tfsess', model_fname))
        ret._init_neural_network()
        ret.saver.restore(ret.session, tf_session_fname)
        return ret

    def train(self,
              das,
              trees,
              data_portion=1.0,
              valid_das=None,
              valid_trees=None):
        """Run training on the given training data.

        @param das: name of source file with training DAs, or list of DAs
        @param trees: name of source file with corresponding trees/sentences, or list of trees
        @param data_portion: portion of the training data to be used (defaults to 1.0)
        @param valid_das: validation data DAs
        @param valid_trees: list of lists of corresponding paraphrases (same length as valid_das)
        """

        log_info('Training reranking classifier...')

        # initialize training
        self._init_training(das, trees, data_portion)
        if self.mode in ['tokens', 'tagged_lemmas'
                         ] and valid_trees is not None:
            valid_trees = [
                self._tokens_to_flat_trees(
                    paraphrases, use_tags=self.mode == 'tagged_lemmas')
                for paraphrases in valid_trees
            ]

        # start training
        top_comb_cost = float('nan')

        for iter_no in xrange(1, self.passes + 1):
            self.train_order = range(len(self.train_trees))
            if self.randomize:
                rnd.shuffle(self.train_order)
            pass_cost, pass_diff = self._training_pass(iter_no)

            if self.validation_freq and iter_no > self.min_passes and iter_no % self.validation_freq == 0:

                valid_diff = 0
                if valid_das:
                    valid_diff = np.sum([
                        np.sum(self.dist_to_da(d, t))
                        for d, t in zip(valid_das, valid_trees)
                    ])

                # cost combining validation and training data performance
                # (+ "real" cost with negligible weight)
                comb_cost = 1000 * valid_diff + 100 * pass_diff + pass_cost
                log_info('Combined validation cost: %8.3f' % comb_cost)

                # if we have the best model so far, save it as a checkpoint (overwrite previous)
                if math.isnan(top_comb_cost) or comb_cost < top_comb_cost:
                    top_comb_cost = comb_cost
                    self._save_checkpoint()

        # restore last checkpoint (best performance on devel data)
        self.restore_checkpoint()

    def classify(self, trees):
        """Classify the tree -- get DA slot-value pairs and DA type to which the tree
        corresponds (as 1/0 array).
        """
        if self.tree_embs:
            inputs = np.array(
                [self.tree_embs.get_embeddings(tree) for tree in trees])
        else:
            inputs = self.tree_vect.transform(
                [self.tree_feats.get_features(tree, {}) for tree in trees])
        fd = {}
        self._add_inputs_to_feed_dict(inputs, fd)
        results = self.session.run(self.outputs, feed_dict=fd)
        # normalize & binarize the result
        return np.array([[1. if r > 0 else 0. for r in result]
                         for result in results])

    def _normalize_da(self, da):
        if isinstance(da,
                      tuple):  # if DA is actually context + DA, ignore context
            da = da[1]
        if self.delex_slots:  # delexicalize the DA if needed
            da = da.get_delexicalized(self.delex_slots)
        return da

    def init_run(self, da):
        """Remember the current DA for subsequent runs of `dist_to_cur_da`."""
        self.cur_da = self._normalize_da(da)
        da_bin = self.da_vect.transform(
            [self.da_feats.get_features(None, {'da': self.cur_da})])[0]
        self.cur_da_bin = da_bin != 0

    def dist_to_da(self, da, trees):
        """Return Hamming distance of given trees to the given DA.

        @param da: the DA as the base of the Hamming distance measure
        @param trees: list of trees to measure the distance
        @return: list of Hamming distances for each tree
        """
        da = self._normalize_da(da)
        da_bin = self.da_vect.transform(
            [self.da_feats.get_features(None, {'da': da})])[0]
        da_bin = da_bin != 0
        covered = self.classify(trees)
        return [sum(abs(c - da_bin)) for c in covered]

    def dist_to_cur_da(self, trees):
        """Return Hamming distance of given trees to the current DA (set in `init_run`).

        @param trees: list of trees to measure the distance
        @return: list of Hamming distances for each tree
        """
        da_bin = self.cur_da_bin
        covered = self.classify(trees)
        return [sum(abs(c - da_bin)) for c in covered]

    def _init_training(self, das, trees, data_portion):
        """Initialize training.

        Store input data, initialize 1-hot feature representations for input and output and
        transform training data accordingly, initialize the classification neural network.

        @param das: name of source file with training DAs, or list of DAs
        @param trees: name of source file with corresponding trees/sentences, or list of trees
        @param data_portion: portion of the training data to be used (0.0-1.0)
        """
        # read input from files or take it directly from parameters
        if not isinstance(das, list):
            log_info('Reading DAs from ' + das + '...')
            das = read_das(das)
        if not isinstance(trees, list):
            log_info('Reading t-trees from ' + trees + '...')
            ttree_doc = read_ttrees(trees)
            if self.mode == 'tokens':
                tokens = tokens_from_doc(ttree_doc, self.language,
                                         self.selector)
                trees = self._tokens_to_flat_trees(tokens)
            elif self.mode == 'tagged_lemmas':
                tls = tagged_lemmas_from_doc(ttree_doc, self.language,
                                             self.selector)
                trees = self._tokens_to_flat_trees(tls, use_tags=True)
            else:
                trees = trees_from_doc(ttree_doc, self.language, self.selector)
        elif self.mode in ['tokens', 'tagged_lemmas']:
            trees = self._tokens_to_flat_trees(
                trees, use_tags=self.mode == 'tagged_lemmas')

        # make training data smaller if necessary
        train_size = int(round(data_portion * len(trees)))
        self.train_trees = trees[:train_size]
        self.train_das = das[:train_size]

        # ignore contexts, if they are contained in the DAs
        if isinstance(self.train_das[0], tuple):
            self.train_das = [da for (context, da) in self.train_das]
        # delexicalize if DAs are lexicalized and we don't want that
        if self.delex_slots:
            self.train_das = [
                da.get_delexicalized(self.delex_slots) for da in self.train_das
            ]

        # add empty tree + empty DA to training data
        # (i.e. forbid the network to keep any of its outputs "always-on")
        train_size += 1
        self.train_trees.append(TreeData())
        empty_da = DA.parse('inform()')
        self.train_das.append(empty_da)

        self.train_order = range(len(self.train_trees))
        log_info('Using %d training instances.' % train_size)

        # initialize input features/embeddings
        if self.tree_embs:
            self.dict_size = self.tree_embs.init_dict(self.train_trees)
            self.X = np.array([
                self.tree_embs.get_embeddings(tree)
                for tree in self.train_trees
            ])
        else:
            self.tree_feats = Features(['node: presence t_lemma formeme'])
            self.tree_vect = DictVectorizer(sparse=False,
                                            binarize_numeric=True)
            self.X = [
                self.tree_feats.get_features(tree, {})
                for tree in self.train_trees
            ]
            self.X = self.tree_vect.fit_transform(self.X)

        # initialize output features
        self.da_feats = Features(['dat: dat_presence', 'svp: svp_presence'])
        self.da_vect = DictVectorizer(sparse=False, binarize_numeric=True)
        self.y = [
            self.da_feats.get_features(None, {'da': da})
            for da in self.train_das
        ]
        self.y = self.da_vect.fit_transform(self.y)
        log_info('Number of binary classes: %d.' %
                 len(self.da_vect.get_feature_names()))

        # initialize I/O shapes
        if not self.tree_embs:
            self.input_shape = list(self.X[0].shape)
        else:
            self.input_shape = self.tree_embs.get_embeddings_shape()
        self.num_outputs = len(self.da_vect.get_feature_names())

        # initialize NN classifier
        self._init_neural_network()
        # initialize the NN variables
        self.session.run(tf.global_variables_initializer())

    def _tokens_to_flat_trees(self, sents, use_tags=False):
        """Use sentences (pairs token-tag) read from Treex files and convert them into flat
        trees (each token has a node right under the root, lemma is the token, formeme is 'x').
        Uses TokenEmbeddingSeq2SeqExtract conversion there and back.

        @param sents: sentences to be converted
        @param use_tags: use tags in the embeddings? (only for lemma-tag pairs in training, \
            not testing)
        @return: a list of flat trees
        """
        tree_embs = (TokenEmbeddingSeq2SeqExtract(cfg=self.cfg) if not use_tags
                     else TaggedLemmasEmbeddingSeq2SeqExtract(cfg=self.cfg))
        tree_embs.init_dict(sents)
        # no postprocessing, i.e. keep lowercasing/plural splitting if set in the configuration
        return [
            tree_embs.ids_to_tree(tree_embs.get_embeddings(sent),
                                  postprocess=False) for sent in sents
        ]

    def _init_neural_network(self):
        """Create the neural network for classification, according to the self.nn_shape
        parameter (as set in configuration)."""

        # set TensorFlow random seed
        tf.set_random_seed(rnd.randint(-sys.maxint, sys.maxint))

        self.targets = tf.placeholder(tf.float32, [None, self.num_outputs],
                                      name='targets')

        with tf.variable_scope(self.scope_name):

            # feedforward networks
            if self.nn_shape.startswith('ff'):
                self.inputs = tf.placeholder(tf.float32,
                                             [None] + self.input_shape,
                                             name='inputs')
                num_ff_layers = 2
                if self.nn_shape[-1] in ['0', '1', '3', '4']:
                    num_ff_layers = int(self.nn_shape[-1])
                self.outputs = self._ff_layers('ff', num_ff_layers,
                                               self.inputs)

            # RNNs
            elif self.nn_shape.startswith('rnn'):
                self.initial_state = tf.placeholder(tf.float32,
                                                    [None, self.emb_size])
                self.inputs = [
                    tf.placeholder(tf.int32, [None], name=('enc_inp-%d' % i))
                    for i in xrange(self.input_shape[0])
                ]
                self.cell = tf.contrib.rnn.BasicLSTMCell(self.emb_size)
                self.outputs = self._rnn('rnn', self.inputs)

        # the cost as computed by TF actually adds a "fake" sigmoid layer on top
        # (or is computed as if there were a sigmoid layer on top)
        self.cost = tf.reduce_mean(
            tf.reduce_sum(
                tf.nn.sigmoid_cross_entropy_with_logits(logits=self.outputs,
                                                        labels=self.targets,
                                                        name='CE'), 1))

        # NB: this would have been the "true" cost function, if there were a "real" sigmoid layer on top.
        # However, it is not numerically stable in practice, so we have to use the TF function.
        # self.cost = tf.reduce_mean(tf.reduce_sum(self.targets * -tf.log(self.outputs)
        #                                          + (1 - self.targets) * -tf.log(1 - self.outputs), 1))

        self.optimizer = tf.train.AdamOptimizer(self.alpha)
        self.train_func = self.optimizer.minimize(self.cost)

        # Tensorboard summaries
        if self.train_summary_dir:
            self.loss_summary_reranker = tf.summary.scalar(
                "loss_reranker", self.cost)
            self.train_summary_op = tf.summary.merge(
                [self.loss_summary_reranker])

        # initialize session
        session_config = None
        if self.max_cores:
            session_config = tf.ConfigProto(
                inter_op_parallelism_threads=self.max_cores,
                intra_op_parallelism_threads=self.max_cores)
        self.session = tf.Session(config=session_config)

        # this helps us load/save the model
        self.saver = tf.train.Saver(tf.global_variables())
        if self.train_summary_dir:  # Tensorboard summary writer
            self.train_summary_writer = tf.summary.FileWriter(
                os.path.join(self.train_summary_dir, "reranker"),
                self.session.graph)

    def _ff_layers(self, name, num_layers, X):
        width = [np.prod(self.input_shape)] + (
            num_layers * [self.num_hidden_units]) + [self.num_outputs]
        # the last layer should be a sigmoid, but TF simulates it for us in cost computation
        # so the output is "unnormalized sigmoids"
        activ = (num_layers * [tf.tanh]) + [tf.identity]
        Y = X
        for i in xrange(num_layers + 1):
            w = tf.get_variable(
                name + ('-w%d' % i), (width[i], width[i + 1]),
                initializer=tf.random_normal_initializer(stddev=0.1))
            b = tf.get_variable(name + ('-b%d' % i), (width[i + 1], ),
                                initializer=tf.constant_initializer())
            Y = activ[i](tf.matmul(Y, w) + b)
        return Y

    def _rnn(self, name, enc_inputs):
        encoder_cell = tf.contrib.rnn.EmbeddingWrapper(self.cell,
                                                       self.dict_size,
                                                       self.emb_size)
        encoder_outputs, encoder_state = tf.contrib.rnn.static_rnn(
            encoder_cell, enc_inputs, dtype=tf.float32)

        # TODO for historical reasons, the last layer uses both output and state.
        # try this just with outputs (might work exactly the same)
        if isinstance(self.cell.state_size, tf.contrib.rnn.LSTMStateTuple):
            state_size = self.cell.state_size.c + self.cell.state_size.h
            final_input = tf.concat(axis=1,
                                    values=encoder_state)  # concat c + h
        else:
            state_size = self.cell.state_size
            final_input = encoder_state

        w = tf.get_variable(
            name + '-w', (state_size, self.num_outputs),
            initializer=tf.random_normal_initializer(stddev=0.1))
        b = tf.get_variable(name + 'b', (self.num_outputs, ),
                            initializer=tf.constant_initializer())
        return tf.matmul(final_input, w) + b

    def _batches(self):
        """Create batches from the input; use as iterator."""
        for i in xrange(0, len(self.train_order), self.batch_size):
            yield self.train_order[i:i + self.batch_size]

    def _add_inputs_to_feed_dict(self, inputs, fd):

        if self.nn_shape.startswith('rnn'):
            fd[self.initial_state] = np.zeros([inputs.shape[0], self.emb_size])
            sliced_inputs = np.squeeze(np.array(
                np.split(np.array([ex for ex in inputs if ex is not None]),
                         len(inputs[0]),
                         axis=1)),
                                       axis=2)
            for input_, slice_ in zip(self.inputs, sliced_inputs):
                fd[input_] = slice_
        else:
            fd[self.inputs] = inputs

    def _training_pass(self, pass_no):
        """Perform one training pass through the whole training data, print statistics."""

        pass_start_time = time.time()

        log_debug('\n***\nTR %05d:' % pass_no)
        log_debug("Train order: " + str(self.train_order))

        pass_cost = 0
        pass_diff = 0

        for tree_nos in self._batches():

            log_debug('TREE-NOS: ' + str(tree_nos))
            log_debug("\n".join(
                unicode(self.train_trees[i]) + "\n" +
                unicode(self.train_das[i]) for i in tree_nos))
            log_debug('Y: ' + str(self.y[tree_nos]))

            fd = {self.targets: self.y[tree_nos]}
            self._add_inputs_to_feed_dict(self.X[tree_nos], fd)
            if self.train_summary_dir:  # also compute Tensorboard summaries
                results, cost, _, train_summary_op = self.session.run(
                    [
                        self.outputs, self.cost, self.train_func,
                        self.train_summary_op
                    ],
                    feed_dict=fd)
            else:
                results, cost, _ = self.session.run(
                    [self.outputs, self.cost, self.train_func], feed_dict=fd)
            bin_result = np.array([[1. if r > 0 else 0. for r in result]
                                   for result in results])

            log_debug('R: ' + str(bin_result))
            log_debug('COST: %f' % cost)
            log_debug('DIFF: %d' %
                      np.sum(np.abs(self.y[tree_nos] - bin_result)))

            pass_cost += cost
            pass_diff += np.sum(np.abs(self.y[tree_nos] - bin_result))

        # print and return statistics
        self._print_pass_stats(
            pass_no,
            datetime.timedelta(seconds=(time.time() - pass_start_time)),
            pass_cost, pass_diff)
        if self.train_summary_dir:  # Tensorboard: iteration summary
            self.train_summary_writer.add_summary(train_summary_op, pass_no)

        return pass_cost, pass_diff

    def _print_pass_stats(self, pass_no, time, cost, diff):
        log_info('PASS %03d: duration %s, cost %f, diff %d' %
                 (pass_no, str(time), cost, diff))

    def evaluate_file(self, das_file, ttree_file):
        """Evaluate the reranking classifier on a given pair of DA/tree files (show the
        total Hamming distance and total number of DAIs)

        @param das_file: DA file path
        @param ttree_file: trees/sentences file path
        @return: a tuple (total DAIs, distance)
        """
        das = read_das(das_file)
        ttree_doc = read_ttrees(ttree_file)
        if self.mode == 'tokens':
            tokens = tokens_from_doc(ttree_doc, self.language, self.selector)
            trees = self._tokens_to_flat_trees(tokens)
        elif self.mode == 'tagged_lemmas':
            tls = tagged_lemmas_from_doc(ttree_doc, self.language,
                                         self.selector)
            trees = self._tokens_to_flat_trees(tls)
        else:
            trees = trees_from_doc(ttree_doc, self.language, self.selector)

        da_len = 0
        dist = 0

        for da, tree in zip(das, trees):
            da_len += len(da)
            dist += self.dist_to_da(da, [tree])[0]

        return da_len, dist
Example #7
0
    def _init_training(self, das, trees, data_portion):
        """Initialize training.

        Store input data, initialize 1-hot feature representations for input and output and
        transform training data accordingly, initialize the classification neural network.

        @param das: name of source file with training DAs, or list of DAs
        @param trees: name of source file with corresponding trees/sentences, or list of trees
        @param data_portion: portion of the training data to be used (0.0-1.0)
        """
        # read input from files or take it directly from parameters
        if not isinstance(das, list):
            log_info('Reading DAs from ' + das + '...')
            das = read_das(das)
        if not isinstance(trees, list):
            log_info('Reading t-trees from ' + trees + '...')
            ttree_doc = read_ttrees(trees)
            if self.mode == 'tokens':
                tokens = tokens_from_doc(ttree_doc, self.language,
                                         self.selector)
                trees = self._tokens_to_flat_trees(tokens)
            elif self.mode == 'tagged_lemmas':
                tls = tagged_lemmas_from_doc(ttree_doc, self.language,
                                             self.selector)
                trees = self._tokens_to_flat_trees(tls, use_tags=True)
            else:
                trees = trees_from_doc(ttree_doc, self.language, self.selector)
        elif self.mode in ['tokens', 'tagged_lemmas']:
            trees = self._tokens_to_flat_trees(
                trees, use_tags=self.mode == 'tagged_lemmas')

        # make training data smaller if necessary
        train_size = int(round(data_portion * len(trees)))
        self.train_trees = trees[:train_size]
        self.train_das = das[:train_size]

        # ignore contexts, if they are contained in the DAs
        if isinstance(self.train_das[0], tuple):
            self.train_das = [da for (context, da) in self.train_das]
        # delexicalize if DAs are lexicalized and we don't want that
        if self.delex_slots:
            self.train_das = [
                da.get_delexicalized(self.delex_slots) for da in self.train_das
            ]

        # add empty tree + empty DA to training data
        # (i.e. forbid the network to keep any of its outputs "always-on")
        train_size += 1
        self.train_trees.append(TreeData())
        empty_da = DA.parse('inform()')
        self.train_das.append(empty_da)

        self.train_order = range(len(self.train_trees))
        log_info('Using %d training instances.' % train_size)

        # initialize input features/embeddings
        if self.tree_embs:
            self.dict_size = self.tree_embs.init_dict(self.train_trees)
            self.X = np.array([
                self.tree_embs.get_embeddings(tree)
                for tree in self.train_trees
            ])
        else:
            self.tree_feats = Features(['node: presence t_lemma formeme'])
            self.tree_vect = DictVectorizer(sparse=False,
                                            binarize_numeric=True)
            self.X = [
                self.tree_feats.get_features(tree, {})
                for tree in self.train_trees
            ]
            self.X = self.tree_vect.fit_transform(self.X)

        # initialize output features
        self.da_feats = Features(['dat: dat_presence', 'svp: svp_presence'])
        self.da_vect = DictVectorizer(sparse=False, binarize_numeric=True)
        self.y = [
            self.da_feats.get_features(None, {'da': da})
            for da in self.train_das
        ]
        self.y = self.da_vect.fit_transform(self.y)
        log_info('Number of binary classes: %d.' %
                 len(self.da_vect.get_feature_names()))

        # initialize I/O shapes
        if not self.tree_embs:
            self.input_shape = list(self.X[0].shape)
        else:
            self.input_shape = self.tree_embs.get_embeddings_shape()
        self.num_outputs = len(self.da_vect.get_feature_names())

        # initialize NN classifier
        self._init_neural_network()
        # initialize the NN variables
        self.session.run(tf.global_variables_initializer())
class TreeClassifier(object):
    """A classifier for trees that decides which DAIs are currently represented
    (to be used in limiting candidate generator and/or re-scoring the trees)."""
    def __init__(self, cfg):
        self.language = cfg.get('language', 'en')
        self.selector = cfg.get('selector', '')
        self.tree_embs = cfg.get('nn', '').startswith('emb')
        if self.tree_embs:
            self.tree_embs = TreeEmbeddingExtract(cfg)
            self.emb_size = cfg.get('emb_size', 20)

        self.nn_shape = cfg.get('nn_shape', 'ff')
        self.num_hidden_units = cfg.get('num_hidden_units', 512)
        self.cnn_num_filters = cfg.get('cnn_num_filters', 3)
        self.cnn_filter_length = cfg.get('cnn_filter_length', 3)
        self.init = cfg.get('initialization', 'uniform_glorot10')

        self.passes = cfg.get('passes', 200)
        self.alpha = cfg.get('alpha', 0.1)
        self.randomize = cfg.get('randomize', True)
        self.batch_size = cfg.get('batch_size', 1)

        self.cur_da = None
        self.cur_da_bin = None

    @staticmethod
    def load_from_file(fname):
        log_info('Loading model from ' + fname)
        with file_stream(fname, mode='rb', encoding=None) as fh:
            classif = pickle.load(fh)
        return classif

    def save_to_file(self, fname):
        log_info('Saving model to ' + fname)
        with file_stream(fname, mode='wb', encoding=None) as fh:
            pickle.dump(self, fh, pickle.HIGHEST_PROTOCOL)

    def train(self, das_file, ttree_file, data_portion=1.0):
        """Run training on the given training data."""
        self._init_training(das_file, ttree_file, data_portion)
        for iter_no in xrange(1, self.passes + 1):
            self.train_order = range(len(self.train_trees))
            if self.randomize:
                rnd.shuffle(self.train_order)
            self._training_pass(iter_no)

    def classify(self, trees):
        """Classify the tree -- get DA slot-value pairs and DA type to which the tree
        corresponds (as 1/0 array).

        This does not have a lot of practical use here, see is_subset_of_da.
        """
        if self.tree_embs:
            X = np.array(
                [self.tree_embs.get_embeddings(tree) for tree in trees])
        else:
            X = self.tree_vect.transform(
                [self.tree_feats.get_features(tree, {}) for tree in trees])
        # binarize the result
        return np.array([[1. if r > 0.5 else 0. for r in result]
                         for result in self.classif.classif(X)])

    def is_subset_of_da(self, da, trees):
        """Given a DA and an array of trees, this gives a boolean array indicating which
        trees currently cover/describe a subset of the DA.

        @param da: the input DA against which the trees should be tested
        @param trees: the trees to test against the DA
        @return: boolean array, with True where the tree covers/describes a subset of the DA
        """
        # get 1-hot representation of the DA
        da_bin = self.da_vect.transform(
            [self.da_feats.get_features(None, {'da': da})])[0]
        # convert it to array of booleans
        da_bin = da_bin != 0
        # classify the trees
        covered = self.classify(trees)
        # decide whether 1's in their 1-hot vectors are subsets of True's in da_bin
        return [((c != 0) | da_bin == da_bin).all() for c in covered]

    def init_run(self, da):
        """Remember the current DA for subsequent runs of `is_subset_of_cur_da`."""
        self.cur_da = da
        da_bin = self.da_vect.transform(
            [self.da_feats.get_features(None, {'da': da})])[0]
        self.cur_da_bin = da_bin != 0

    def is_subset_of_cur_da(self, trees):
        """Same as `is_subset_of_da`, but using `self.cur_da` set via `init_run`."""
        da_bin = self.cur_da_bin
        covered = self.classify(trees)
        return [((c != 0) | da_bin == da_bin).all() for c in covered]

    def corresponds_to_cur_da(self, trees):
        """Given an array of trees, this gives a boolean array indicating which
        trees currently cover exactly the current DA (set via `init_run`).

        @param trees: the trees to test against the current DA
        @return: boolean array, with True where the tree covers/describes a subset of the current DA
        """
        da_bin = self.cur_da_bin
        covered = self.classify(trees)
        return [((c != 0) == da_bin).all() for c in covered]

    def _init_training(self, das_file, ttree_file, data_portion):
        """Initialize training.

        Store input data, initialize 1-hot feature representations for input and output and
        transform training data accordingly, initialize the classification neural network.
        """
        # read input
        log_info('Reading DAs from ' + das_file + '...')
        das = read_das(das_file)
        log_info('Reading t-trees from ' + ttree_file + '...')
        ttree_doc = read_ttrees(ttree_file)
        trees = trees_from_doc(ttree_doc, self.language, self.selector)

        # make training data smaller if necessary
        train_size = int(round(data_portion * len(trees)))
        self.train_trees = trees[:train_size]
        self.train_das = das[:train_size]

        # add empty tree + empty DA to training data
        # (i.e. forbid the network to keep any of its outputs "always-on")
        train_size += 1
        self.train_trees.append(TreeData())
        empty_da = DA.parse('inform()')
        self.train_das.append(empty_da)

        self.train_order = range(len(self.train_trees))
        log_info('Using %d training instances.' % train_size)

        # initialize input features/embeddings
        if self.tree_embs:
            self.dict_size = self.tree_embs.init_dict(self.train_trees)
            self.X = np.array([
                self.tree_embs.get_embeddings(tree)
                for tree in self.train_trees
            ])
        else:
            self.tree_feats = Features(['node: presence t_lemma formeme'])
            self.tree_vect = DictVectorizer(sparse=False,
                                            binarize_numeric=True)
            self.X = [
                self.tree_feats.get_features(tree, {})
                for tree in self.train_trees
            ]
            self.X = self.tree_vect.fit_transform(self.X)

        # initialize output features
        self.da_feats = Features(['dat: dat_presence', 'svp: svp_presence'])
        self.da_vect = DictVectorizer(sparse=False, binarize_numeric=True)
        self.y = [
            self.da_feats.get_features(None, {'da': da})
            for da in self.train_das
        ]
        self.y = self.da_vect.fit_transform(self.y)

        # initialize I/O shapes
        self.input_shape = [list(self.X[0].shape)]
        self.num_outputs = len(self.da_vect.get_feature_names())

        # initialize NN classifier
        self._init_neural_network()

    def _init_neural_network(self):
        """Create the neural network for classification, according to the self.nn_shape
        parameter (as set in configuration)."""
        layers = []
        if self.tree_embs:
            layers.append([
                Embedding('emb', self.dict_size, self.emb_size, 'uniform_005')
            ])

        # feedforward networks
        if self.nn_shape.startswith('ff'):
            if self.tree_embs:
                layers.append([Flatten('flat')])
            num_ff_layers = 2
            if self.nn_shape[-1] in ['0', '1', '3', '4']:
                num_ff_layers = int(self.nn_shape[-1])
            layers += self._ff_layers('ff', num_ff_layers)

        # convolutional networks
        elif 'conv' in self.nn_shape or 'pool' in self.nn_shape:
            assert self.tree_embs  # convolution makes no sense without embeddings
            num_conv = 0
            if 'conv' in self.nn_shape:
                num_conv = 1
            if 'conv2' in self.nn_shape:
                num_conv = 2
            pooling = None
            if 'maxpool' in self.nn_shape:
                pooling = T.max
            elif 'avgpool' in self.nn_shape:
                pooling = T.mean
            layers += self._conv_layers('conv', num_conv, pooling)
            layers.append([Flatten('flat')])
            layers += self._ff_layers('ff', 1)

        # input types: integer 3D for tree embeddings (batch + 2D embeddings),
        #              float 2D (matrix) for binary input (batch + features)
        input_types = (T.itensor3, ) if self.tree_embs else (T.fmatrix, )

        # create the network, connect layers
        self.classif = ClassifNN(layers,
                                 self.input_shape,
                                 input_types,
                                 normgrad=False)
        log_info("Network shape:\n\n" + str(self.classif))

    def _ff_layers(self, name, num_layers):
        ret = []
        for i in xrange(num_layers):
            ret.append([
                FeedForward(name + str(i + 1), self.num_hidden_units, T.tanh,
                            self.init)
            ])
        ret.append([
            FeedForward('output', self.num_outputs, T.nnet.sigmoid, self.init)
        ])
        return ret

    def _conv_layers(self, name, num_layers=1, pooling=None):
        ret = []
        for i in xrange(num_layers):
            ret.append([
                Conv1D(name + str(i + 1),
                       filter_length=self.cnn_filter_length,
                       num_filters=self.cnn_num_filters,
                       init=self.init,
                       activation=T.tanh)
            ])
        if pooling is not None:
            ret.append(
                [Pool1D(name + str(i + 1) + 'pool', pooling_func=pooling)])
        return ret

    def batches(self):
        for i in xrange(0, len(self.train_order), self.batch_size):
            yield self.train_order[i:i + self.batch_size]

    def _training_pass(self, pass_no):
        """Perform one training pass through the whole training data, print statistics."""

        pass_start_time = time.time()

        log_debug('\n***\nTR %05d:' % pass_no)
        log_debug("Train order: " + str(self.train_order))

        pass_cost = 0
        pass_diff = 0

        for tree_nos in self.batches():

            log_debug('TREE-NOS: ' + str(tree_nos))
            log_debug("\n".join(
                unicode(self.train_trees[i]) + "\n" +
                unicode(self.train_das[i]) for i in tree_nos))
            log_debug('Y: ' + str(self.y[tree_nos]))

            results = self.classif.classif(self.X[tree_nos])
            cost_gcost = self.classif.update(self.X[tree_nos],
                                             self.y[tree_nos], self.alpha)
            bin_result = np.array([[1. if r > 0.5 else 0. for r in result]
                                   for result in results])

            log_debug('R: ' + str(bin_result))
            log_debug('COST: %f' % cost_gcost[0])
            log_debug('DIFF: %d' %
                      np.sum(np.abs(self.y[tree_nos] - bin_result)))

            pass_cost += cost_gcost[0]
            pass_diff += np.sum(np.abs(self.y[tree_nos] - bin_result))

        # print and return statistics
        self._print_pass_stats(
            pass_no,
            datetime.timedelta(seconds=(time.time() - pass_start_time)),
            pass_cost, pass_diff)

    def _print_pass_stats(self, pass_no, time, cost, diff):
        log_info('PASS %03d: duration %s, cost %f, diff %d' %
                 (pass_no, str(time), cost, diff))
Example #9
0
class EmbNNRanker(NNRanker):
    """A ranker using MR and tree embeddings in a NN."""

    def __init__(self, cfg):
        super(EmbNNRanker, self).__init__(cfg)
        self.emb_size = cfg.get('emb_size', 20)
        self.nn_shape = cfg.get('nn_shape', 'ff')
        self.normgrad = cfg.get('normgrad', False)

        self.cnn_num_filters = cfg.get('cnn_num_filters', 3)
        self.cnn_filter_length = cfg.get('cnn_filter_length', 3)

        # 'emb' = embeddings for both, 'emb_trees' = embeddings for tree only, 1-hot DA
        # 'emb_tree', 'emb_prev' = tree-only embeddings
        self.da_embs = cfg.get('nn', 'emb') == 'emb'

        self.tree_embs = TreeEmbeddingExtract(cfg)

        if self.da_embs:
            self.da_embs = DAEmbeddingExtract(cfg)
        else:
            self.da_feats = Features(['dat: dat_presence', 'svp: svp_presence'])
            self.vectorizer = None

    def _init_training(self, das_file, ttree_file, data_portion):
        super(EmbNNRanker, self)._init_training(das_file, ttree_file, data_portion)
        self._init_dict()
        self._init_neural_network()

        self.train_feats = [self._extract_feats(tree, da)
                            for tree, da in zip(self.train_trees, self.train_das)]

        self.w_after_iter = []
        self.update_weights_sum()

    def _init_dict(self):
        """Initialize word -> integer dictionaries, starting from a minimum
        valid value, always adding a new integer to unknown values to prevent
        clashes among different types of inputs."""

        # avoid dictionary clashes between DAs and tree embeddings
        # – remember current highest index number
        dict_ord = None

        # DA embeddings
        if self.da_embs:
            dict_ord = self.da_embs.init_dict(self.train_das)

        # DA one-hot representation
        else:
            X = []
            for da, tree in zip(self.train_das, self.train_trees):
                X.append(self.da_feats.get_features(tree, {'da': da}))

            self.vectorizer = DictVectorizer(sparse=False, binarize_numeric=True)
            self.vectorizer.fit(X)

        # tree embeddings
        # remember last dictionary key to initialize embeddings with enough rows
        self.dict_size = self.tree_embs.init_dict(self.train_trees, dict_ord)

    def _score(self, cand_embs):
        return self.nn.score([cand_embs[0]], [cand_embs[1]])[0]

    def _extract_feats(self, tree, da):
        """Extract DA and tree embeddings (return as a pair)."""
        if self.da_embs:
            # DA embeddings
            da_repr = self.da_embs.get_embeddings(da)
        else:
            # DA one-hot representation
            da_repr = self.vectorizer.transform([self.da_feats.get_features(tree, {'da': da})])[0]

        # tree embeddings
        tree_emb_idxs = self.tree_embs.get_embeddings(tree)

        return (da_repr, tree_emb_idxs)

    def _init_neural_network(self):
        # initial layer – tree embeddings & DA 1-hot or embeddings
        # input shapes don't contain the batch dimension, but the input Theano types do!
        if self.da_embs:
            input_shapes = (self.da_embs.get_embeddings_shape(),
                            self.tree_embs.get_embeddings_shape())
            input_types = (T.itensor3, T.itensor3)
            layers = [[Embedding('emb_da', self.dict_size, self.emb_size, 'uniform_005'),
                       Embedding('emb_tree', self.dict_size, self.emb_size, 'uniform_005')]]
        else:
            input_shapes = ([len(self.vectorizer.get_feature_names())],
                            self.tree_embs.get_embeddings_shape())
            input_types = (T.fmatrix, T.itensor3)
            layers = [[Identity('id_da'),
                       Embedding('emb_tree', self.dict_size, self.emb_size, 'uniform_005')]]

        # plain feed-forward networks
        if self.nn_shape.startswith('ff'):

            layers += [[Flatten('flat_da'), Flatten('flat_tree')], [Concat('concat')]]
            num_ff_layers = 2
            if self.nn_shape[-1] in ['3', '4']:
                num_ff_layers = int(self.nn_shape[-1])
            layers += self._ff_layers('ff', num_ff_layers, perc_layer=True)

        # convolution with or without max/avg-pooling
        elif self.nn_shape.startswith('conv'):

            num_conv_layers = 2 if self.nn_shape.startswith('conv2') else 1
            pooling = None
            if 'maxpool' in self.nn_shape:
                pooling = T.max
            elif 'avgpool' in self.nn_shape:
                pooling = T.mean

            if self.da_embs:
                da_layers = self._conv_layers('conv_da', num_conv_layers, pooling=pooling)
            else:
                da_layers = self._id_layers('id_da',
                                            num_conv_layers + (1 if pooling is not None else 0))
            tree_layers = self._conv_layers('conv_tree', num_conv_layers, pooling=pooling)

            for da_layer, tree_layer in zip(da_layers, tree_layers):
                layers.append([da_layer[0], tree_layer[0]])
            layers += [[Flatten('flat_da'), Flatten('flat_tree')], [Concat('concat')]]
            layers += self._ff_layers('ff', 2, perc_layer=True)

        # max-pooling without convolution
        elif 'maxpool-ff' in self.nn_shape:
            layers += [[Pool1D('mp_da') if self.da_embs else Identity('id_da'),
                        Pool1D('mp_trees')]
                       [Concat('concat')], [Flatten('flat')]]
            layers += self._ff_layers('ff', 2, perc_layer=True),

        # dot-product FF network
        elif 'dot' in self.nn_shape:
            # with max or average pooling
            if 'maxpool' in self.nn_shape or 'avgpool' in self.nn_shape:
                pooling = T.mean if 'avgpool' in self.nn_shape else T.max
                layers += [[Pool1D('mp_da', pooling_func=pooling)
                            if self.da_embs else Identity('id_da'),
                            Pool1D('mp_tree', pooling_func=pooling)]]
            layers += [[Flatten('flat_da') if self.da_embs else Identity('id_da'),
                        Flatten('flat_tree')]]

            num_ff_layers = int(self.nn_shape[-1]) if self.nn_shape[-1] in ['2', '3', '4'] else 1
            for da_layer, tree_layer in zip(self._ff_layers('ff_da', num_ff_layers),
                                            self._ff_layers('ff_tree', num_ff_layers)):
                layers.append([da_layer[0], tree_layer[0]])
            layers.append([DotProduct('dot')])

        # input: batch * word * sub-embeddings
        self.nn = RankNN(layers, input_shapes, input_types, self.normgrad)
        log_info("Network shape:\n\n" + str(self.nn))

    def _conv_layers(self, name, num_layers=1, pooling=None):
        ret = []
        for i in range(num_layers):
            ret.append([Conv1D(name + str(i + 1),
                               filter_length=self.cnn_filter_length,
                               num_filters=self.cnn_num_filters,
                               init=self.init, activation=T.tanh)])
        if pooling is not None:
            ret.append([Pool1D(name + str(i + 1) + 'pool', pooling_func=pooling)])
        return ret

    def _id_layers(self, name, num_layers):
        ret = []
        for i in range(num_layers):
            ret.append([Identity(name + str(i + 1))])
        return ret

    def _update_nn(self, bad_feats, good_feats, rate):
        """Changing the NN update call to support arrays of parameters."""
        # TODO: this is just adding another dimension to fit the parallelized scoring
        # (even if updates are not parallelized). Make it nicer.
        bad_feats = ([bad_feats[0]], [bad_feats[1]])
        good_feats = ([good_feats[0]], [good_feats[1]])

        cost_gcost = self.nn.update(*(bad_feats + good_feats + (rate,)))
        log_debug('Cost:' + str(cost_gcost[0]))
        param_vals = [param.get_value() for param in self.nn.params]
        log_debug('Param norms : ' + str(self._l2s(param_vals)))
        log_debug('Gparam norms: ' + str(self._l2s(cost_gcost[1:])))

    def _embs_to_str(self):
        out = ""
        da_emb = self.nn.layers[0][0].e.get_value()
        tree_emb = self.nn.layers[0][1].e.get_value()
        for idx, emb in enumerate(da_emb):
            for key, val in list(self.dict_slot.items()):
                if val == idx:
                    out += key + ',' + ','.join([("%f" % d) for d in emb]) + "\n"
            for key, val in list(self.dict_value.items()):
                if val == idx:
                    out += key + ',' + ','.join([("%f" % d) for d in emb]) + "\n"
        for idx, emb in enumerate(tree_emb):
            for key, val in list(self.dict_t_lemma.items()):
                if val == idx:
                    out += str(key) + ',' + ','.join([("%f" % d) for d in emb]) + "\n"
            for key, val in list(self.dict_formeme.items()):
                if val == idx:
                    out += str(key) + ',' + ','.join([("%f" % d) for d in emb]) + "\n"
        return out

    def _l2s(self, params):
        """Compute L2-norm of all members of the given list."""
        return [np.linalg.norm(param) for param in params]

    def store_iter_weights(self):
        """Remember the current weights to be used for averaged perceptron."""
        # fh = open('embs.txt', 'a')
        # print >> fh, '---', self._embs_to_str()
        # fh.close()
        self.w_after_iter.append(self.nn.get_param_values())

    def score_all(self, trees, da):
        cand_embs = [self._extract_feats(tree, da) for tree in trees]
        score = self.nn.score([emb[0] for emb in cand_embs], [emb[1] for emb in cand_embs])
        return np.atleast_1d(score[0])
Example #10
0
from flect.config import Config
from tgen.features import Features
from tgen.futil import trees_from_doc, read_ttrees, read_das
import sys
import timeit
import datetime

if len(sys.argv[1:]) != 3:
    sys.exit('Usage: ./bench_feats.py features_cfg.py trees.yaml.gz das.txt')

print >> sys.stderr, 'Loading...'

cfg = Config(sys.argv[1])
trees = trees_from_doc(read_ttrees(sys.argv[2]), 'en', '')
das = read_das(sys.argv[3])

feats = Features(cfg['features'])


def test_func():
    for tree, da in zip(trees, das):
        feats.get_features(tree, {'da': da})


print >> sys.stderr, 'Running test...'
secs = timeit.timeit('test_func()',
                     setup='from __main__ import test_func',
                     number=10)
td = datetime.timedelta(seconds=secs)
print >> sys.stderr, 'Time taken: %s' % str(td)
Example #11
0
class TreeClassifier(object):
    """A classifier for trees that decides which DAIs are currently represented
    (to be used in limiting candidate generator and/or re-scoring the trees)."""

    def __init__(self, cfg):
        self.language = cfg.get('language', 'en')
        self.selector = cfg.get('selector', '')
        self.tree_embs = cfg.get('nn', '').startswith('emb')
        if self.tree_embs:
            self.tree_embs = TreeEmbeddingExtract(cfg)
            self.emb_size = cfg.get('emb_size', 20)

        self.nn_shape = cfg.get('nn_shape', 'ff')
        self.num_hidden_units = cfg.get('num_hidden_units', 512)
        self.cnn_num_filters = cfg.get('cnn_num_filters', 3)
        self.cnn_filter_length = cfg.get('cnn_filter_length', 3)
        self.init = cfg.get('initialization', 'uniform_glorot10')

        self.passes = cfg.get('passes', 200)
        self.alpha = cfg.get('alpha', 0.1)
        self.randomize = cfg.get('randomize', True)
        self.batch_size = cfg.get('batch_size', 1)

        self.cur_da = None
        self.cur_da_bin = None

    @staticmethod
    def load_from_file(fname):
        log_info('Loading model from ' + fname)
        with file_stream(fname, mode='rb', encoding=None) as fh:
            classif = pickle.load(fh)
        return classif

    def save_to_file(self, fname):
        log_info('Saving model to ' + fname)
        with file_stream(fname, mode='wb', encoding=None) as fh:
            pickle.dump(self, fh, pickle.HIGHEST_PROTOCOL)

    def train(self, das_file, ttree_file, data_portion=1.0):
        """Run training on the given training data."""
        self._init_training(das_file, ttree_file, data_portion)
        for iter_no in xrange(1, self.passes + 1):
            self.train_order = range(len(self.train_trees))
            if self.randomize:
                rnd.shuffle(self.train_order)
            self._training_pass(iter_no)

    def classify(self, trees):
        """Classify the tree -- get DA slot-value pairs and DA type to which the tree
        corresponds (as 1/0 array).

        This does not have a lot of practical use here, see is_subset_of_da.
        """
        if self.tree_embs:
            X = np.array([self.tree_embs.get_embeddings(tree) for tree in trees])
        else:
            X = self.tree_vect.transform([self.tree_feats.get_features(tree, {}) for tree in trees])
        # binarize the result
        return np.array([[1. if r > 0.5 else 0. for r in result]
                         for result in self.classif.classif(X)])

    def is_subset_of_da(self, da, trees):
        """Given a DA and an array of trees, this gives a boolean array indicating which
        trees currently cover/describe a subset of the DA.

        @param da: the input DA against which the trees should be tested
        @param trees: the trees to test against the DA
        @return: boolean array, with True where the tree covers/describes a subset of the DA
        """
        # get 1-hot representation of the DA
        da_bin = self.da_vect.transform([self.da_feats.get_features(None, {'da': da})])[0]
        # convert it to array of booleans
        da_bin = da_bin != 0
        # classify the trees
        covered = self.classify(trees)
        # decide whether 1's in their 1-hot vectors are subsets of True's in da_bin
        return [((c != 0) | da_bin == da_bin).all() for c in covered]

    def init_run(self, da):
        """Remember the current DA for subsequent runs of `is_subset_of_cur_da`."""
        self.cur_da = da
        da_bin = self.da_vect.transform([self.da_feats.get_features(None, {'da': da})])[0]
        self.cur_da_bin = da_bin != 0

    def is_subset_of_cur_da(self, trees):
        """Same as `is_subset_of_da`, but using `self.cur_da` set via `init_run`."""
        da_bin = self.cur_da_bin
        covered = self.classify(trees)
        return [((c != 0) | da_bin == da_bin).all() for c in covered]

    def corresponds_to_cur_da(self, trees):
        """Given an array of trees, this gives a boolean array indicating which
        trees currently cover exactly the current DA (set via `init_run`).

        @param trees: the trees to test against the current DA
        @return: boolean array, with True where the tree covers/describes a subset of the current DA
        """
        da_bin = self.cur_da_bin
        covered = self.classify(trees)
        return [((c != 0) == da_bin).all() for c in covered]

    def _init_training(self, das_file, ttree_file, data_portion):
        """Initialize training.

        Store input data, initialize 1-hot feature representations for input and output and
        transform training data accordingly, initialize the classification neural network.
        """
        # read input
        log_info('Reading DAs from ' + das_file + '...')
        das = read_das(das_file)
        log_info('Reading t-trees from ' + ttree_file + '...')
        ttree_doc = read_ttrees(ttree_file)
        trees = trees_from_doc(ttree_doc, self.language, self.selector)

        # make training data smaller if necessary
        train_size = int(round(data_portion * len(trees)))
        self.train_trees = trees[:train_size]
        self.train_das = das[:train_size]

        # add empty tree + empty DA to training data
        # (i.e. forbid the network to keep any of its outputs "always-on")
        train_size += 1
        self.train_trees.append(TreeData())
        empty_da = DialogueAct()
        empty_da.parse('inform()')
        self.train_das.append(empty_da)

        self.train_order = range(len(self.train_trees))
        log_info('Using %d training instances.' % train_size)

        # initialize input features/embeddings
        if self.tree_embs:
            self.dict_size = self.tree_embs.init_dict(self.train_trees)
            self.X = np.array([self.tree_embs.get_embeddings(tree) for tree in self.train_trees])
        else:
            self.tree_feats = Features(['node: presence t_lemma formeme'])
            self.tree_vect = DictVectorizer(sparse=False, binarize_numeric=True)
            self.X = [self.tree_feats.get_features(tree, {}) for tree in self.train_trees]
            self.X = self.tree_vect.fit_transform(self.X)

        # initialize output features
        self.da_feats = Features(['dat: dat_presence', 'svp: svp_presence'])
        self.da_vect = DictVectorizer(sparse=False, binarize_numeric=True)
        self.y = [self.da_feats.get_features(None, {'da': da}) for da in self.train_das]
        self.y = self.da_vect.fit_transform(self.y)

        # initialize I/O shapes
        self.input_shape = [list(self.X[0].shape)]
        self.num_outputs = len(self.da_vect.get_feature_names())

        # initialize NN classifier
        self._init_neural_network()

    def _init_neural_network(self):
        """Create the neural network for classification, according to the self.nn_shape
        parameter (as set in configuration)."""
        layers = []
        if self.tree_embs:
            layers.append([Embedding('emb', self.dict_size, self.emb_size, 'uniform_005')])

        # feedforward networks
        if self.nn_shape.startswith('ff'):
            if self.tree_embs:
                layers.append([Flatten('flat')])
            num_ff_layers = 2
            if self.nn_shape[-1] in ['0', '1', '3', '4']:
                num_ff_layers = int(self.nn_shape[-1])
            layers += self._ff_layers('ff', num_ff_layers)

        # convolutional networks
        elif 'conv' in self.nn_shape or 'pool' in self.nn_shape:
            assert self.tree_embs  # convolution makes no sense without embeddings
            num_conv = 0
            if 'conv' in self.nn_shape:
                num_conv = 1
            if 'conv2' in self.nn_shape:
                num_conv = 2
            pooling = None
            if 'maxpool' in self.nn_shape:
                pooling = T.max
            elif 'avgpool' in self.nn_shape:
                pooling = T.mean
            layers += self._conv_layers('conv', num_conv, pooling)
            layers.append([Flatten('flat')])
            layers += self._ff_layers('ff', 1)

        # input types: integer 3D for tree embeddings (batch + 2D embeddings),
        #              float 2D (matrix) for binary input (batch + features)
        input_types = (T.itensor3,) if self.tree_embs else (T.fmatrix,)

        # create the network, connect layers
        self.classif = ClassifNN(layers, self.input_shape, input_types, normgrad=False)
        log_info("Network shape:\n\n" + str(self.classif))

    def _ff_layers(self, name, num_layers):
        ret = []
        for i in xrange(num_layers):
            ret.append([FeedForward(name + str(i + 1), self.num_hidden_units, T.tanh, self.init)])
        ret.append([FeedForward('output', self.num_outputs, T.nnet.sigmoid, self.init)])
        return ret

    def _conv_layers(self, name, num_layers=1, pooling=None):
        ret = []
        for i in xrange(num_layers):
            ret.append([Conv1D(name + str(i + 1),
                               filter_length=self.cnn_filter_length,
                               num_filters=self.cnn_num_filters,
                               init=self.init, activation=T.tanh)])
        if pooling is not None:
            ret.append([Pool1D(name + str(i + 1) + 'pool', pooling_func=pooling)])
        return ret

    def batches(self):
        for i in xrange(0, len(self.train_order), self.batch_size):
            yield self.train_order[i: i + self.batch_size]

    def _training_pass(self, pass_no):
        """Perform one training pass through the whole training data, print statistics."""

        pass_start_time = time.time()

        log_debug('\n***\nTR %05d:' % pass_no)
        log_debug("Train order: " + str(self.train_order))

        pass_cost = 0
        pass_diff = 0

        for tree_nos in self.batches():

            log_debug('TREE-NOS: ' + str(tree_nos))
            log_debug("\n".join(unicode(self.train_trees[i]) + "\n" + unicode(self.train_das[i])
                                for i in tree_nos))
            log_debug('Y: ' + str(self.y[tree_nos]))

            results = self.classif.classif(self.X[tree_nos])
            cost_gcost = self.classif.update(self.X[tree_nos], self.y[tree_nos], self.alpha)
            bin_result = np.array([[1. if r > 0.5 else 0. for r in result] for result in results])

            log_debug('R: ' + str(bin_result))
            log_debug('COST: %f' % cost_gcost[0])
            log_debug('DIFF: %d' % np.sum(np.abs(self.y[tree_nos] - bin_result)))

            pass_cost += cost_gcost[0]
            pass_diff += np.sum(np.abs(self.y[tree_nos] - bin_result))

        # print and return statistics
        self._print_pass_stats(pass_no, datetime.timedelta(seconds=(time.time() - pass_start_time)),
                               pass_cost, pass_diff)

    def _print_pass_stats(self, pass_no, time, cost, diff):
        log_info('PASS %03d: duration %s, cost %f, diff %d' % (pass_no, str(time), cost, diff))
Example #12
0
class EmbNNRanker(NNRanker):
    """A ranker using MR and tree embeddings in a NN."""

    def __init__(self, cfg):
        super(EmbNNRanker, self).__init__(cfg)
        self.emb_size = cfg.get('emb_size', 20)
        self.nn_shape = cfg.get('nn_shape', 'ff')
        self.normgrad = cfg.get('normgrad', False)

        self.cnn_num_filters = cfg.get('cnn_num_filters', 3)
        self.cnn_filter_length = cfg.get('cnn_filter_length', 3)

        # 'emb' = embeddings for both, 'emb_trees' = embeddings for tree only, 1-hot DA
        # 'emb_tree', 'emb_prev' = tree-only embeddings
        self.da_embs = cfg.get('nn', 'emb') == 'emb'

        self.tree_embs = TreeEmbeddingExtract(cfg)

        if self.da_embs:
            self.da_embs = DAEmbeddingExtract(cfg)
        else:
            self.da_feats = Features(['dat: dat_presence', 'svp: svp_presence'])
            self.vectorizer = None

    def _init_training(self, das_file, ttree_file, data_portion):
        super(EmbNNRanker, self)._init_training(das_file, ttree_file, data_portion)
        self._init_dict()
        self._init_neural_network()

        self.train_feats = [self._extract_feats(tree, da)
                            for tree, da in zip(self.train_trees, self.train_das)]

        self.w_after_iter = []
        self.update_weights_sum()

    def _init_dict(self):
        """Initialize word -> integer dictionaries, starting from a minimum
        valid value, always adding a new integer to unknown values to prevent
        clashes among different types of inputs."""

        # avoid dictionary clashes between DAs and tree embeddings
        # – remember current highest index number
        dict_ord = None

        # DA embeddings
        if self.da_embs:
            dict_ord = self.da_embs.init_dict(self.train_das)

        # DA one-hot representation
        else:
            X = []
            for da, tree in zip(self.train_das, self.train_trees):
                X.append(self.da_feats.get_features(tree, {'da': da}))

            self.vectorizer = DictVectorizer(sparse=False, binarize_numeric=True)
            self.vectorizer.fit(X)

        # tree embeddings
        # remember last dictionary key to initialize embeddings with enough rows
        self.dict_size = self.tree_embs.init_dict(self.train_trees, dict_ord)

    def _score(self, cand_embs):
        return self.nn.score([cand_embs[0]], [cand_embs[1]])[0]

    def _extract_feats(self, tree, da):
        """Extract DA and tree embeddings (return as a pair)."""
        if self.da_embs:
            # DA embeddings
            da_repr = self.da_embs.get_embeddings(da)
        else:
            # DA one-hot representation
            da_repr = self.vectorizer.transform([self.da_feats.get_features(tree, {'da': da})])[0]

        # tree embeddings
        tree_emb_idxs = self.tree_embs.get_embeddings(tree)

        return (da_repr, tree_emb_idxs)

    def _init_neural_network(self):
        # initial layer – tree embeddings & DA 1-hot or embeddings
        # input shapes don't contain the batch dimension, but the input Theano types do!
        if self.da_embs:
            input_shapes = (self.da_embs.get_embeddings_shape(),
                            self.tree_embs.get_embeddings_shape())
            input_types = (T.itensor3, T.itensor3)
            layers = [[Embedding('emb_da', self.dict_size, self.emb_size, 'uniform_005'),
                       Embedding('emb_tree', self.dict_size, self.emb_size, 'uniform_005')]]
        else:
            input_shapes = ([len(self.vectorizer.get_feature_names())],
                            self.tree_embs.get_embeddings_shape())
            input_types = (T.fmatrix, T.itensor3)
            layers = [[Identity('id_da'),
                       Embedding('emb_tree', self.dict_size, self.emb_size, 'uniform_005')]]

        # plain feed-forward networks
        if self.nn_shape.startswith('ff'):

            layers += [[Flatten('flat_da'), Flatten('flat_tree')], [Concat('concat')]]
            num_ff_layers = 2
            if self.nn_shape[-1] in ['3', '4']:
                num_ff_layers = int(self.nn_shape[-1])
            layers += self._ff_layers('ff', num_ff_layers, perc_layer=True)

        # convolution with or without max/avg-pooling
        elif self.nn_shape.startswith('conv'):

            num_conv_layers = 2 if self.nn_shape.startswith('conv2') else 1
            pooling = None
            if 'maxpool' in self.nn_shape:
                pooling = T.max
            elif 'avgpool' in self.nn_shape:
                pooling = T.mean

            if self.da_embs:
                da_layers = self._conv_layers('conv_da', num_conv_layers, pooling=pooling)
            else:
                da_layers = self._id_layers('id_da',
                                            num_conv_layers + (1 if pooling is not None else 0))
            tree_layers = self._conv_layers('conv_tree', num_conv_layers, pooling=pooling)

            for da_layer, tree_layer in zip(da_layers, tree_layers):
                layers.append([da_layer[0], tree_layer[0]])
            layers += [[Flatten('flat_da'), Flatten('flat_tree')], [Concat('concat')]]
            layers += self._ff_layers('ff', 2, perc_layer=True)

        # max-pooling without convolution
        elif 'maxpool-ff' in self.nn_shape:
            layers += [[Pool1D('mp_da') if self.da_embs else Identity('id_da'),
                        Pool1D('mp_trees')]
                       [Concat('concat')], [Flatten('flat')]]
            layers += self._ff_layers('ff', 2, perc_layer=True),

        # dot-product FF network
        elif 'dot' in self.nn_shape:
            # with max or average pooling
            if 'maxpool' in self.nn_shape or 'avgpool' in self.nn_shape:
                pooling = T.mean if 'avgpool' in self.nn_shape else T.max
                layers += [[Pool1D('mp_da', pooling_func=pooling)
                            if self.da_embs else Identity('id_da'),
                            Pool1D('mp_tree', pooling_func=pooling)]]
            layers += [[Flatten('flat_da') if self.da_embs else Identity('id_da'),
                        Flatten('flat_tree')]]

            num_ff_layers = int(self.nn_shape[-1]) if self.nn_shape[-1] in ['2', '3', '4'] else 1
            for da_layer, tree_layer in zip(self._ff_layers('ff_da', num_ff_layers),
                                            self._ff_layers('ff_tree', num_ff_layers)):
                layers.append([da_layer[0], tree_layer[0]])
            layers.append([DotProduct('dot')])

        # input: batch * word * sub-embeddings
        self.nn = RankNN(layers, input_shapes, input_types, self.normgrad)
        log_info("Network shape:\n\n" + str(self.nn))

    def _conv_layers(self, name, num_layers=1, pooling=None):
        ret = []
        for i in xrange(num_layers):
            ret.append([Conv1D(name + str(i + 1),
                               filter_length=self.cnn_filter_length,
                               num_filters=self.cnn_num_filters,
                               init=self.init, activation=T.tanh)])
        if pooling is not None:
            ret.append([Pool1D(name + str(i + 1) + 'pool', pooling_func=pooling)])
        return ret

    def _id_layers(self, name, num_layers):
        ret = []
        for i in xrange(num_layers):
            ret.append([Identity(name + str(i + 1))])
        return ret

    def _update_nn(self, bad_feats, good_feats, rate):
        """Changing the NN update call to support arrays of parameters."""
        # TODO: this is just adding another dimension to fit the parallelized scoring
        # (even if updates are not parallelized). Make it nicer.
        bad_feats = ([bad_feats[0]], [bad_feats[1]])
        good_feats = ([good_feats[0]], [good_feats[1]])

        cost_gcost = self.nn.update(*(bad_feats + good_feats + (rate,)))
        log_debug('Cost:' + str(cost_gcost[0]))
        param_vals = [param.get_value() for param in self.nn.params]
        log_debug('Param norms : ' + str(self._l2s(param_vals)))
        log_debug('Gparam norms: ' + str(self._l2s(cost_gcost[1:])))

    def _embs_to_str(self):
        out = ""
        da_emb = self.nn.layers[0][0].e.get_value()
        tree_emb = self.nn.layers[0][1].e.get_value()
        for idx, emb in enumerate(da_emb):
            for key, val in self.dict_slot.items():
                if val == idx:
                    out += key + ',' + ','.join([("%f" % d) for d in emb]) + "\n"
            for key, val in self.dict_value.items():
                if val == idx:
                    out += key + ',' + ','.join([("%f" % d) for d in emb]) + "\n"
        for idx, emb in enumerate(tree_emb):
            for key, val in self.dict_t_lemma.items():
                if val == idx:
                    out += str(key) + ',' + ','.join([("%f" % d) for d in emb]) + "\n"
            for key, val in self.dict_formeme.items():
                if val == idx:
                    out += str(key) + ',' + ','.join([("%f" % d) for d in emb]) + "\n"
        return out

    def _l2s(self, params):
        """Compute L2-norm of all members of the given list."""
        return [np.linalg.norm(param) for param in params]

    def store_iter_weights(self):
        """Remember the current weights to be used for averaged perceptron."""
        # fh = open('embs.txt', 'a')
        # print >> fh, '---', self._embs_to_str()
        # fh.close()
        self.w_after_iter.append(self.nn.get_param_values())

    def score_all(self, trees, da):
        cand_embs = [self._extract_feats(tree, da) for tree in trees]
        score = self.nn.score([emb[0] for emb in cand_embs], [emb[1] for emb in cand_embs])
        return np.atleast_1d(score[0])
Example #13
0
class Reranker(object):

    def __init__(self, cfg):
        self.cfg = cfg
        self.language = cfg.get('language', 'en')
        self.selector = cfg.get('selector', '')

        self.mode = cfg.get('mode', 'tokens' if cfg.get('use_tokens') else 'trees')

        self.da_feats = Features(['dat: dat_presence', 'svp: svp_presence'])
        self.da_vect = DictVectorizer(sparse=False, binarize_numeric=True)

        self.cur_da = None
        self.cur_da_bin = None

        self.delex_slots = cfg.get('delex_slots', None)
        if self.delex_slots:
            self.delex_slots = set(self.delex_slots.split(','))

    @staticmethod
    def get_model_type(cfg):
        """Return the correct model class according to the config."""
        if cfg.get('model') == 'e2e_patterns':
            from tgen.e2e.slot_error import E2EPatternClassifier
            return E2EPatternClassifier
        return RerankingClassifier

    @staticmethod
    def load_from_file(reranker_fname):
        """Detect correct model type and start loading."""
        model_type = RerankingClassifier  # default to classifier
        with file_stream(reranker_fname, 'rb', encoding=None) as fh:
            data = pickle.load(fh)
            if isinstance(data, type):
                from tgen.e2e.slot_error import E2EPatternClassifier
                model_type = data
        return model_type.load_from_file(reranker_fname)

    def save_to_file(self, reranker_fname):
        raise NotImplementedError()

    def get_all_settings(self):
        raise NotImplementedError()

    def classify(self, trees):
        raise NotImplementedError()

    def train(self, das, trees, data_portion=1.0, valid_das=None, valid_trees=None):
        raise NotImplementedError()

    def _normalize_da(self, da):
        if isinstance(da, tuple):  # if DA is actually context + DA, ignore context
            da = da[1]
        if self.delex_slots:  # delexicalize the DA if needed
            da = da.get_delexicalized(self.delex_slots)
        return da

    def init_run(self, da):
        """Remember the current DA for subsequent runs of `dist_to_cur_da`."""
        self.cur_da = self._normalize_da(da)
        da_bin = self.da_vect.transform([self.da_feats.get_features(None, {'da': self.cur_da})])[0]
        self.cur_da_bin = da_bin != 0

    def dist_to_da(self, da, trees, return_classif=False):
        """Return Hamming distance of given trees to the given DA.

        @param da: the DA as the base of the Hamming distance measure
        @param trees: list of trees to measure the distance
        @return: list of Hamming distances for each tree (+ resulting classification if return_classif)
        """
        self.init_run(da)
        ret = self.dist_to_cur_da(trees, return_classif)
        self.cur_da = None
        self.cur_da_bin = None
        return ret

    def dist_to_cur_da(self, trees, return_classif=False):
        """Return Hamming distance of given trees to the current DA (set in `init_run`).

        @param trees: list of trees to measure the distance
        @return: list of Hamming distances for each tree (+ resulting classification if return_classif)
        """
        da_bin = self.cur_da_bin
        covered = self.classify(trees)
        dist = [sum(abs(c - da_bin)) for c in covered]
        if return_classif:
            return dist, [[f for f, c_ in zip(self.da_vect.feature_names_, c) if c_] for c in covered]
        return dist
Example #14
0
class RerankingClassifier(TFModel):
    """A classifier for trees that decides which DAIs are currently represented
    (to be used in limiting candidate generator and/or re-scoring the trees)."""

    def __init__(self, cfg):

        super(RerankingClassifier, self).__init__(scope_name='rerank-' +
                                                  cfg.get('scope_suffix', ''))
        self.cfg = cfg
        self.language = cfg.get('language', 'en')
        self.selector = cfg.get('selector', '')
        self.tree_embs = cfg.get('nn', '').startswith('emb')
        if self.tree_embs:
            self.tree_embs = TreeEmbeddingClassifExtract(cfg)
            self.emb_size = cfg.get('emb_size', 50)
        self.mode = cfg.get('mode', 'tokens' if cfg.get('use_tokens') else 'trees')

        self.nn_shape = cfg.get('nn_shape', 'ff')
        self.num_hidden_units = cfg.get('num_hidden_units', 512)

        self.passes = cfg.get('passes', 200)
        self.min_passes = cfg.get('min_passes', 0)
        self.alpha = cfg.get('alpha', 0.1)
        self.randomize = cfg.get('randomize', True)
        self.batch_size = cfg.get('batch_size', 1)

        self.validation_freq = cfg.get('validation_freq', 10)
        self.max_cores = cfg.get('max_cores')
        self.cur_da = None
        self.cur_da_bin = None
        self.checkpoint_path = None

        self.delex_slots = cfg.get('delex_slots', None)
        if self.delex_slots:
            self.delex_slots = set(self.delex_slots.split(','))

        # Train Summaries
        self.train_summary_dir = cfg.get('tb_summary_dir', None)
        if self.train_summary_dir:
            self.loss_summary_reranker = None
            self.train_summary_op = None
            self.train_summary_writer = None

    def save_to_file(self, model_fname):
        """Save the classifier  to a file (actually two files, one for configuration and one
        for the TensorFlow graph, which must be stored separately).

        @param model_fname: file name (for the configuration file); TF graph will be stored with a \
            different extension
        """
        model_fname = self.tf_check_filename(model_fname)
        log_info("Saving classifier to %s..." % model_fname)
        with file_stream(model_fname, 'wb', encoding=None) as fh:
            pickle.dump(self.get_all_settings(), fh, protocol=pickle.HIGHEST_PROTOCOL)
        tf_session_fname = re.sub(r'(.pickle)?(.gz)?$', '.tfsess', model_fname)
        if hasattr(self, 'checkpoint_path') and self.checkpoint_path:
            self.restore_checkpoint()
            shutil.rmtree(os.path.dirname(self.checkpoint_path))
        self.saver.save(self.session, tf_session_fname)

    def get_all_settings(self):
        """Get all settings except the trained model parameters (to be stored in a pickle)."""
        data = {'cfg': self.cfg,
                'da_feats': self.da_feats,
                'da_vect': self.da_vect,
                'tree_embs': self.tree_embs,
                'input_shape': self.input_shape,
                'num_outputs': self.num_outputs, }
        if self.tree_embs:
            data['dict_size'] = self.dict_size
        else:
            data['tree_feats'] = self.tree_feats
            data['tree_vect'] = self.tree_vect
        return data

    def _save_checkpoint(self):
        """Save a checkpoint to a temporary path; set `self.checkpoint_path` to the path
        where it is saved; if called repeatedly, will always overwrite the last checkpoint."""
        if not self.checkpoint_path:
            path = tempfile.mkdtemp(suffix="", prefix="tftreecl-")
            self.checkpoint_path = os.path.join(path, "ckpt")
        log_info('Saving checkpoint to %s' % self.checkpoint_path)
        self.saver.save(self.session, self.checkpoint_path)

    def restore_checkpoint(self):
        if not self.checkpoint_path:
            return
        self.saver.restore(self.session, self.checkpoint_path)

    @staticmethod
    def load_from_file(model_fname):
        """Load the reranker from a file (actually two files, one for configuration and one
        for the TensorFlow graph, which must be stored separately).

        @param model_fname: file name (for the configuration file); TF graph must be stored with a \
            different extension
        """
        log_info("Loading reranker from %s..." % model_fname)
        with file_stream(model_fname, 'rb', encoding=None) as fh:
            data = pickle.load(fh)
            ret = RerankingClassifier(cfg=data['cfg'])
            ret.load_all_settings(data)

        # re-build TF graph and restore the TF session
        tf_session_fname = os.path.abspath(re.sub(r'(.pickle)?(.gz)?$', '.tfsess', model_fname))
        ret._init_neural_network()
        ret.saver.restore(ret.session, tf_session_fname)
        return ret

    def train(self, das, trees, data_portion=1.0, valid_das=None, valid_trees=None):
        """Run training on the given training data.

        @param das: name of source file with training DAs, or list of DAs
        @param trees: name of source file with corresponding trees/sentences, or list of trees
        @param data_portion: portion of the training data to be used (defaults to 1.0)
        @param valid_das: validation data DAs
        @param valid_trees: list of lists of corresponding paraphrases (same length as valid_das)
        """

        log_info('Training reranking classifier...')

        # initialize training
        self._init_training(das, trees, data_portion)
        if self.mode in ['tokens', 'tagged_lemmas'] and valid_trees is not None:
            valid_trees = [self._tokens_to_flat_trees(paraphrases,
                                                      use_tags=self.mode == 'tagged_lemmas')
                           for paraphrases in valid_trees]

        # start training
        top_comb_cost = float('nan')

        for iter_no in xrange(1, self.passes + 1):
            self.train_order = range(len(self.train_trees))
            if self.randomize:
                rnd.shuffle(self.train_order)
            pass_cost, pass_diff = self._training_pass(iter_no)

            if self.validation_freq and iter_no > self.min_passes and iter_no % self.validation_freq == 0:

                valid_diff = 0
                if valid_das:
                    valid_diff = np.sum([np.sum(self.dist_to_da(d, t))
                                         for d, t in zip(valid_das, valid_trees)])

                # cost combining validation and training data performance
                # (+ "real" cost with negligible weight)
                comb_cost = 1000 * valid_diff + 100 * pass_diff + pass_cost
                log_info('Combined validation cost: %8.3f' % comb_cost)

                # if we have the best model so far, save it as a checkpoint (overwrite previous)
                if math.isnan(top_comb_cost) or comb_cost < top_comb_cost:
                    top_comb_cost = comb_cost
                    self._save_checkpoint()

        # restore last checkpoint (best performance on devel data)
        self.restore_checkpoint()

    def classify(self, trees):
        """Classify the tree -- get DA slot-value pairs and DA type to which the tree
        corresponds (as 1/0 array).
        """
        if self.tree_embs:
            inputs = np.array([self.tree_embs.get_embeddings(tree) for tree in trees])
        else:
            inputs = self.tree_vect.transform([self.tree_feats.get_features(tree, {})
                                               for tree in trees])
        fd = {}
        self._add_inputs_to_feed_dict(inputs, fd)
        results = self.session.run(self.outputs, feed_dict=fd)
        # normalize & binarize the result
        return np.array([[1. if r > 0 else 0. for r in result] for result in results])

    def _normalize_da(self, da):
        if isinstance(da, tuple):  # if DA is actually context + DA, ignore context
            da = da[1]
        if self.delex_slots:  # delexicalize the DA if needed
            da = da.get_delexicalized(self.delex_slots)
        return da

    def init_run(self, da):
        """Remember the current DA for subsequent runs of `dist_to_cur_da`."""
        self.cur_da = self._normalize_da(da)
        da_bin = self.da_vect.transform([self.da_feats.get_features(None, {'da': self.cur_da})])[0]
        self.cur_da_bin = da_bin != 0

    def dist_to_da(self, da, trees):
        """Return Hamming distance of given trees to the given DA.

        @param da: the DA as the base of the Hamming distance measure
        @param trees: list of trees to measure the distance
        @return: list of Hamming distances for each tree
        """
        da = self._normalize_da(da)
        da_bin = self.da_vect.transform([self.da_feats.get_features(None, {'da': da})])[0]
        da_bin = da_bin != 0
        covered = self.classify(trees)
        return [sum(abs(c - da_bin)) for c in covered]

    def dist_to_cur_da(self, trees):
        """Return Hamming distance of given trees to the current DA (set in `init_run`).

        @param trees: list of trees to measure the distance
        @return: list of Hamming distances for each tree
        """
        da_bin = self.cur_da_bin
        covered = self.classify(trees)
        return [sum(abs(c - da_bin)) for c in covered]

    def _init_training(self, das, trees, data_portion):
        """Initialize training.

        Store input data, initialize 1-hot feature representations for input and output and
        transform training data accordingly, initialize the classification neural network.

        @param das: name of source file with training DAs, or list of DAs
        @param trees: name of source file with corresponding trees/sentences, or list of trees
        @param data_portion: portion of the training data to be used (0.0-1.0)
        """
        # read input from files or take it directly from parameters
        if not isinstance(das, list):
            log_info('Reading DAs from ' + das + '...')
            das = read_das(das)
        if not isinstance(trees, list):
            log_info('Reading t-trees from ' + trees + '...')
            ttree_doc = read_ttrees(trees)
            if self.mode == 'tokens':
                tokens = tokens_from_doc(ttree_doc, self.language, self.selector)
                trees = self._tokens_to_flat_trees(tokens)
            elif self.mode == 'tagged_lemmas':
                tls = tagged_lemmas_from_doc(ttree_doc, self.language, self.selector)
                trees = self._tokens_to_flat_trees(tls, use_tags=True)
            else:
                trees = trees_from_doc(ttree_doc, self.language, self.selector)
        elif self.mode in ['tokens', 'tagged_lemmas']:
            trees = self._tokens_to_flat_trees(trees, use_tags=self.mode == 'tagged_lemmas')

        # make training data smaller if necessary
        train_size = int(round(data_portion * len(trees)))
        self.train_trees = trees[:train_size]
        self.train_das = das[:train_size]

        # ignore contexts, if they are contained in the DAs
        if isinstance(self.train_das[0], tuple):
            self.train_das = [da for (context, da) in self.train_das]
        # delexicalize if DAs are lexicalized and we don't want that
        if self.delex_slots:
            self.train_das = [da.get_delexicalized(self.delex_slots) for da in self.train_das]

        # add empty tree + empty DA to training data
        # (i.e. forbid the network to keep any of its outputs "always-on")
        train_size += 1
        self.train_trees.append(TreeData())
        empty_da = DA.parse('inform()')
        self.train_das.append(empty_da)

        self.train_order = range(len(self.train_trees))
        log_info('Using %d training instances.' % train_size)

        # initialize input features/embeddings
        if self.tree_embs:
            self.dict_size = self.tree_embs.init_dict(self.train_trees)
            self.X = np.array([self.tree_embs.get_embeddings(tree) for tree in self.train_trees])
        else:
            self.tree_feats = Features(['node: presence t_lemma formeme'])
            self.tree_vect = DictVectorizer(sparse=False, binarize_numeric=True)
            self.X = [self.tree_feats.get_features(tree, {}) for tree in self.train_trees]
            self.X = self.tree_vect.fit_transform(self.X)

        # initialize output features
        self.da_feats = Features(['dat: dat_presence', 'svp: svp_presence'])
        self.da_vect = DictVectorizer(sparse=False, binarize_numeric=True)
        self.y = [self.da_feats.get_features(None, {'da': da}) for da in self.train_das]
        self.y = self.da_vect.fit_transform(self.y)
        log_info('Number of binary classes: %d.' % len(self.da_vect.get_feature_names()))

        # initialize I/O shapes
        if not self.tree_embs:
            self.input_shape = list(self.X[0].shape)
        else:
            self.input_shape = self.tree_embs.get_embeddings_shape()
        self.num_outputs = len(self.da_vect.get_feature_names())

        # initialize NN classifier
        self._init_neural_network()
        # initialize the NN variables
        self.session.run(tf.global_variables_initializer())

    def _tokens_to_flat_trees(self, sents, use_tags=False):
        """Use sentences (pairs token-tag) read from Treex files and convert them into flat
        trees (each token has a node right under the root, lemma is the token, formeme is 'x').
        Uses TokenEmbeddingSeq2SeqExtract conversion there and back.

        @param sents: sentences to be converted
        @param use_tags: use tags in the embeddings? (only for lemma-tag pairs in training, \
            not testing)
        @return: a list of flat trees
        """
        tree_embs = (TokenEmbeddingSeq2SeqExtract(cfg=self.cfg)
                     if not use_tags
                     else TaggedLemmasEmbeddingSeq2SeqExtract(cfg=self.cfg))
        tree_embs.init_dict(sents)
        # no postprocessing, i.e. keep lowercasing/plural splitting if set in the configuration
        return [tree_embs.ids_to_tree(tree_embs.get_embeddings(sent), postprocess=False)
                for sent in sents]

    def _init_neural_network(self):
        """Create the neural network for classification, according to the self.nn_shape
        parameter (as set in configuration)."""

        # set TensorFlow random seed
        tf.set_random_seed(rnd.randint(-sys.maxint, sys.maxint))

        self.targets = tf.placeholder(tf.float32, [None, self.num_outputs], name='targets')

        with tf.variable_scope(self.scope_name):

            # feedforward networks
            if self.nn_shape.startswith('ff'):
                self.inputs = tf.placeholder(tf.float32, [None] + self.input_shape, name='inputs')
                num_ff_layers = 2
                if self.nn_shape[-1] in ['0', '1', '3', '4']:
                    num_ff_layers = int(self.nn_shape[-1])
                self.outputs = self._ff_layers('ff', num_ff_layers, self.inputs)

            # RNNs
            elif self.nn_shape.startswith('rnn'):
                self.initial_state = tf.placeholder(tf.float32, [None, self.emb_size])
                self.inputs = [tf.placeholder(tf.int32, [None], name=('enc_inp-%d' % i))
                               for i in xrange(self.input_shape[0])]
                self.cell = tf.contrib.rnn.BasicLSTMCell(self.emb_size)
                self.outputs = self._rnn('rnn', self.inputs)

        # the cost as computed by TF actually adds a "fake" sigmoid layer on top
        # (or is computed as if there were a sigmoid layer on top)
        self.cost = tf.reduce_mean(tf.reduce_sum(
            tf.nn.sigmoid_cross_entropy_with_logits(logits=self.outputs, labels=self.targets, name='CE'), 1))

        # NB: this would have been the "true" cost function, if there were a "real" sigmoid layer on top.
        # However, it is not numerically stable in practice, so we have to use the TF function.
        # self.cost = tf.reduce_mean(tf.reduce_sum(self.targets * -tf.log(self.outputs)
        #                                          + (1 - self.targets) * -tf.log(1 - self.outputs), 1))

        self.optimizer = tf.train.AdamOptimizer(self.alpha)
        self.train_func = self.optimizer.minimize(self.cost)

        # Tensorboard summaries
        if self.train_summary_dir:
            self.loss_summary_reranker = tf.summary.scalar("loss_reranker", self.cost)
            self.train_summary_op = tf.summary.merge([self.loss_summary_reranker])

        # initialize session
        session_config = None
        if self.max_cores:
            session_config = tf.ConfigProto(inter_op_parallelism_threads=self.max_cores,
                                            intra_op_parallelism_threads=self.max_cores)
        self.session = tf.Session(config=session_config)

        # this helps us load/save the model
        self.saver = tf.train.Saver(tf.global_variables())
        if self.train_summary_dir:  # Tensorboard summary writer
            self.train_summary_writer = tf.summary.FileWriter(
                os.path.join(self.train_summary_dir, "reranker"), self.session.graph)

    def _ff_layers(self, name, num_layers, X):
        width = [np.prod(self.input_shape)] + (num_layers * [self.num_hidden_units]) + [self.num_outputs]
        # the last layer should be a sigmoid, but TF simulates it for us in cost computation
        # so the output is "unnormalized sigmoids"
        activ = (num_layers * [tf.tanh]) + [tf.identity]
        Y = X
        for i in xrange(num_layers + 1):
            w = tf.get_variable(name + ('-w%d' % i), (width[i], width[i + 1]),
                                initializer=tf.random_normal_initializer(stddev=0.1))
            b = tf.get_variable(name + ('-b%d' % i), (width[i + 1],),
                                initializer=tf.constant_initializer())
            Y = activ[i](tf.matmul(Y, w) + b)
        return Y

    def _rnn(self, name, enc_inputs):
        encoder_cell = tf.contrib.rnn.EmbeddingWrapper(self.cell, self.dict_size, self.emb_size)
        encoder_outputs, encoder_state = tf.contrib.rnn.static_rnn(encoder_cell, enc_inputs, dtype=tf.float32)

        # TODO for historical reasons, the last layer uses both output and state.
        # try this just with outputs (might work exactly the same)
        if isinstance(self.cell.state_size, tf.contrib.rnn.LSTMStateTuple):
            state_size = self.cell.state_size.c + self.cell.state_size.h
            final_input = tf.concat(axis=1, values=encoder_state)  # concat c + h
        else:
            state_size = self.cell.state_size
            final_input = encoder_state

        w = tf.get_variable(name + '-w', (state_size, self.num_outputs),
                            initializer=tf.random_normal_initializer(stddev=0.1))
        b = tf.get_variable(name + 'b', (self.num_outputs,), initializer=tf.constant_initializer())
        return tf.matmul(final_input, w) + b

    def _batches(self):
        """Create batches from the input; use as iterator."""
        for i in xrange(0, len(self.train_order), self.batch_size):
            yield self.train_order[i: i + self.batch_size]

    def _add_inputs_to_feed_dict(self, inputs, fd):

        if self.nn_shape.startswith('rnn'):
            fd[self.initial_state] = np.zeros([inputs.shape[0], self.emb_size])
            sliced_inputs = np.squeeze(np.array(np.split(np.array([ex for ex in inputs
                                                                   if ex is not None]),
                                                         len(inputs[0]), axis=1)), axis=2)
            for input_, slice_ in zip(self.inputs, sliced_inputs):
                fd[input_] = slice_
        else:
            fd[self.inputs] = inputs

    def _training_pass(self, pass_no):
        """Perform one training pass through the whole training data, print statistics."""

        pass_start_time = time.time()

        log_debug('\n***\nTR %05d:' % pass_no)
        log_debug("Train order: " + str(self.train_order))

        pass_cost = 0
        pass_diff = 0

        for tree_nos in self._batches():

            log_debug('TREE-NOS: ' + str(tree_nos))
            log_debug("\n".join(unicode(self.train_trees[i]) + "\n" + unicode(self.train_das[i])
                                for i in tree_nos))
            log_debug('Y: ' + str(self.y[tree_nos]))

            fd = {self.targets: self.y[tree_nos]}
            self._add_inputs_to_feed_dict(self.X[tree_nos], fd)
            if self.train_summary_dir:  # also compute Tensorboard summaries
                results, cost, _, train_summary_op = self.session.run(
                    [self.outputs, self.cost, self.train_func, self.train_summary_op], feed_dict=fd)
            else:
                results, cost, _ = self.session.run([self.outputs, self.cost, self.train_func],
                                                    feed_dict=fd)
            bin_result = np.array([[1. if r > 0 else 0. for r in result] for result in results])

            log_debug('R: ' + str(bin_result))
            log_debug('COST: %f' % cost)
            log_debug('DIFF: %d' % np.sum(np.abs(self.y[tree_nos] - bin_result)))

            pass_cost += cost
            pass_diff += np.sum(np.abs(self.y[tree_nos] - bin_result))

        # print and return statistics
        self._print_pass_stats(pass_no, datetime.timedelta(seconds=(time.time() - pass_start_time)),
                               pass_cost, pass_diff)
        if self.train_summary_dir:  # Tensorboard: iteration summary
            self.train_summary_writer.add_summary(train_summary_op, pass_no)

        return pass_cost, pass_diff

    def _print_pass_stats(self, pass_no, time, cost, diff):
        log_info('PASS %03d: duration %s, cost %f, diff %d' % (pass_no, str(time), cost, diff))

    def evaluate_file(self, das_file, ttree_file):
        """Evaluate the reranking classifier on a given pair of DA/tree files (show the
        total Hamming distance and total number of DAIs)

        @param das_file: DA file path
        @param ttree_file: trees/sentences file path
        @return: a tuple (total DAIs, distance)
        """
        das = read_das(das_file)
        ttree_doc = read_ttrees(ttree_file)
        if self.mode == 'tokens':
            tokens = tokens_from_doc(ttree_doc, self.language, self.selector)
            trees = self._tokens_to_flat_trees(tokens)
        elif self.mode == 'tagged_lemmas':
            tls = tagged_lemmas_from_doc(ttree_doc, self.language, self.selector)
            trees = self._tokens_to_flat_trees(tls)
        else:
            trees = trees_from_doc(ttree_doc, self.language, self.selector)

        da_len = 0
        dist = 0

        for da, tree in zip(das, trees):
            da_len += len(da)
            dist += self.dist_to_da(da, [tree])[0]

        return da_len, dist
Example #15
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    def _init_training(self, das, trees, data_portion):
        """Initialize training.

        Store input data, initialize 1-hot feature representations for input and output and
        transform training data accordingly, initialize the classification neural network.

        @param das: name of source file with training DAs, or list of DAs
        @param trees: name of source file with corresponding trees/sentences, or list of trees
        @param data_portion: portion of the training data to be used (0.0-1.0)
        """
        # read input from files or take it directly from parameters
        if not isinstance(das, list):
            log_info('Reading DAs from ' + das + '...')
            das = read_das(das)
        if not isinstance(trees, list):
            log_info('Reading t-trees from ' + trees + '...')
            ttree_doc = read_ttrees(trees)
            if self.mode == 'tokens':
                tokens = tokens_from_doc(ttree_doc, self.language, self.selector)
                trees = self._tokens_to_flat_trees(tokens)
            elif self.mode == 'tagged_lemmas':
                tls = tagged_lemmas_from_doc(ttree_doc, self.language, self.selector)
                trees = self._tokens_to_flat_trees(tls, use_tags=True)
            else:
                trees = trees_from_doc(ttree_doc, self.language, self.selector)
        elif self.mode in ['tokens', 'tagged_lemmas']:
            trees = self._tokens_to_flat_trees(trees, use_tags=self.mode == 'tagged_lemmas')

        # make training data smaller if necessary
        train_size = int(round(data_portion * len(trees)))
        self.train_trees = trees[:train_size]
        self.train_das = das[:train_size]

        # ignore contexts, if they are contained in the DAs
        if isinstance(self.train_das[0], tuple):
            self.train_das = [da for (context, da) in self.train_das]
        # delexicalize if DAs are lexicalized and we don't want that
        if self.delex_slots:
            self.train_das = [da.get_delexicalized(self.delex_slots) for da in self.train_das]

        # add empty tree + empty DA to training data
        # (i.e. forbid the network to keep any of its outputs "always-on")
        train_size += 1
        self.train_trees.append(TreeData())
        empty_da = DA.parse('inform()')
        self.train_das.append(empty_da)

        self.train_order = range(len(self.train_trees))
        log_info('Using %d training instances.' % train_size)

        # initialize input features/embeddings
        if self.tree_embs:
            self.dict_size = self.tree_embs.init_dict(self.train_trees)
            self.X = np.array([self.tree_embs.get_embeddings(tree) for tree in self.train_trees])
        else:
            self.tree_feats = Features(['node: presence t_lemma formeme'])
            self.tree_vect = DictVectorizer(sparse=False, binarize_numeric=True)
            self.X = [self.tree_feats.get_features(tree, {}) for tree in self.train_trees]
            self.X = self.tree_vect.fit_transform(self.X)

        # initialize output features
        self.da_feats = Features(['dat: dat_presence', 'svp: svp_presence'])
        self.da_vect = DictVectorizer(sparse=False, binarize_numeric=True)
        self.y = [self.da_feats.get_features(None, {'da': da}) for da in self.train_das]
        self.y = self.da_vect.fit_transform(self.y)
        log_info('Number of binary classes: %d.' % len(self.da_vect.get_feature_names()))

        # initialize I/O shapes
        if not self.tree_embs:
            self.input_shape = list(self.X[0].shape)
        else:
            self.input_shape = self.tree_embs.get_embeddings_shape()
        self.num_outputs = len(self.da_vect.get_feature_names())

        # initialize NN classifier
        self._init_neural_network()
        # initialize the NN variables
        self.session.run(tf.global_variables_initializer())